* Peter Ujfalusi <peter.ujfalusi@xxxxxx> [200212 08:02]: > > > On 11/02/2020 19.16, Tony Lindgren wrote: > > We can have multiple connections on a single McBSP instance configured > > with audio graph card when using TDM (Time Division Multiplexing). Let's > > allow that by configuring dais dynamically. > > It is still one DAI... > If you have multiple codec connected to the same I2S lines, but the > codecs communicate within different time slots, you still have one DAI > on the CPU side, but multiple codecs (codec DAIs) with different TDM slot. OK so subject should say "dodec DAIs" then I guess? > > See Documentation/devicetree/bindings/sound/audio-graph-card.txt and > > Documentation/devicetree/bindings/graph.txt for more details for > > multiple endpoints. > > See the example for 'Multi DAI with DPCM' in audio-graph-card.txt > The PCM3168a have 2 DAIs: playback and capture, but you can have > multiple endpoints within a DAI. Yes this should follow the audio-graph-card.txt example. We end up with mcbsp3 dts node as below on droid4: &mcbsp3 { #sound-dai-cells = <0>; pinctrl-names = "default"; pinctrl-0 = <&mcbsp3_pins>; status = "okay"; ports { mcbsp3_port: port@0 { #address-cells = <1>; #size-cells = <0>; cpu_dai3: endpoint@0 { reg = <0>; dai-format = "dsp_a"; frame-master = <&cpcap_audio_codec1>; bitclock-master = <&cpcap_audio_codec1>; remote-endpoint = <&cpcap_audio_codec1>; }; cpu_dai_mdm: endpoint@1 { reg = <1>; dai-format = "dsp_a"; frame-master = <&cpcap_audio_codec1>; bitclock-master = <&cpcap_audio_codec1>; remote-endpoint = <&mot_mdm6600_audio_codec0>; }; }; }; }; That is pretty much the same as the 'Multi DAI with DPCM' example, with dne dai, and multiple endpoints. I think we still have just one port for one i2s transport on the mcbsp :) Does the above look as what you would expect based on the binding? > > I've tested this with droid4 where cpcap pmic and modem voice are both > > both wired to mcbsp3. I've also tested this on droid4 both with and > > without the pending modem audio codec driver that is waiting for n_gsm > > serdev dependencies to clear. > > What this patch you effectively just creating dummy-dais on top of the > real McBSP DAI. Yes I think this is needed for snd-soc-audio-graph-card, and this allows configuring whatever is needed for the i2s slot. But maybe you have some better way of doing it in mind? > You also rename the DAIs, which might break ams-delta. Oops, that's not good. So should we just keep the old naming if there's only one endpoint? > We still have legacy support in > omap-twl4030.c > omap3pandora.c > osk5912.c > rx51.c > > which will break with the renamed DAI. On the other hand I think the > legacy support can be dropped from them. I'm not sure what all that would take. > I know it was discussed, but can not find the mail: > Can you brief again on the audio connection? Below is a link to a mailing list thread where Sebastian describes the audio connection: https://lkml.org/lkml/2018/3/28/881 > Do you have branch with working code? Yeah I have slightly older set of the patches in my droid4-pending-v5.5 kernel.org git branch with voice calls working. Regards, Tony _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx https://mailman.alsa-project.org/mailman/listinfo/alsa-devel